Sheet metal panel raceway including recesses

ABSTRACT

A raceway element for a rolling-element bearing, the rolling-element bearing having an inner ring, an outer ring, and a plurality of rolling elements that are disposed between the inner ring and the outer ring. The raceway element is configured as an inner ring or as an outer ring, or is configured to be attachable to an inner ring or outer ring of the bearing, wherein at least one surface of the raceway element is configured as a raceway for the rolling elements. The raceway element is formed from a sheet metal panel having at least one recess formed in the surface configured as the raceway.

CROSS-REFERENCE

This application claims priority to German patent application no. 102020 208 272.3 filed on Jul. 2, 2020, the contents of which are fullyincorporated herein by reference.

TECHNOLOGICAL FIELD

The present disclosure relates to a sheet metal raceway element for abearing, and, more specifically, to a sheet metal raceway element for abearing having at least one recess in the raceway surface. Thedisclosure also relates to a bearing including the raceway element and amethod of manufacturing the raceway element.

BACKGROUND

From the prior art, raceways made from thin-walled metal are known forrolling-element bearings, which raceways are formed by rolling andsubsequent deep drawing. For this purpose a pot-shaped raceway blank isgenerated in possibly multiple deep-drawing steps. The pot-shapedraceway blank has a substantially cylindrical shape, including a collarthat is located on the side opposite the closed side of the pot. Thedeep drawing can be effected in a plurality of steps until the desiredheight is achieved for the future raceway. Subsequently a base of thepot-shaped raceway blank thus generated is cut out, and the collargenerated by the deep drawing is removed.

In order for the raceway thus obtained to have the necessary surfaceproperties, further processing steps, such as, for example, hardening,annealing, or other surface treatments may be required in order toobtain the desired material properties for the raceway.

Accordingly a series of machines as well as process steps are requiredfor the manufacturing of the raceway, with the result that, inparticular in the case of small quantities, the manufacturing isuneconomical. In addition, depending on the metal used, such a racewayelement may be relatively heavy and expensive.

SUMMARY

It is therefore an aspect of the present disclosure to provide a racewayelement that can be manufactured with reduced work and material expense.

In the following a raceway element for a rolling-element bearing isdisclosed, wherein the rolling-element bearing comprises an inner ring,an outer ring, and a plurality of rolling elements that are disposedbetween the inner ring and the outer ring, wherein the raceway elementis configured as an inner ring or as an outer ring, or is configured tobe attachable to an inner ring or an outer ring of the bearing, whereinat least one surface of the raceway element is configured as a racewayfor the rolling elements. In order to reduce material and manufacturingcosts, the raceway element is manufactured from a sheet metal panel. Inparticular, the sheet metal panel can already have a surface treatmentrequired for the finished raceway element. Alternatively the surfacetreatment can also be effected on the manufactured raceway elementand/or in an intermediate step of the manufacturing.

Furthermore, at least one recess, in particular a continuous recess, isformed in the surface of the raceway element, which surface is formed asa raceway. Here the at least one recess can be configured as a lubricantreservoir in order to, for example, improve the lubrication conditionsfor the rolling elements. Furthermore, the at least one recess alsomakes it possible to reduce material, which can on the one hand reducethe costs of the raceway element, and on the other hand reduces theweight of the raceway element.

Furthermore, the sheet metal panel can already have the thicknessdesired for the raceway element. In addition, not just a single racewayelement, but rather many raceway elements can be manufactured from themetal plate, which raceway elements can also differ in their dimensions.

The sheet metal panel is preferably manufactured from a metal that issuitable to provide the desired material properties for a raceway. Forthis purpose known steels can be used in particular, such as, forexample, strip steel, construction steel, case hardened steel, ortempered steel. The steel used can preferably be suitable to be weldedin order to make possible, for example, a material-bonded connectionbetween two parts. However, other types of connections, such as, forexample, an interference-fit connection or a friction-fit connection,can also be used. In particular, the sheet metal panel can already beheat-treated and/or surface-treated. The sheet metal panel preferablyhas a thickness between 0.5 mm and 4 mm.

Here a first surface of the raceway element can include a raceway thatinteracts with rolling elements rolling on it. Alternatively the firstsurface of the raceway element can include a sliding surface thatinteracts with another sliding surface, so that the raceway elementsformed as an inner ring or an outer ring, or the element serving as aninner ring and the element serving as an outer ring for the bearing, orthe inner ring and the outer ring of the bearing are rotatable againsteach other.

According to a further embodiment, the raceway element is formed bylaser cutting and/or punching from the sheet metal panel. With the aidof laser cutting, arbitrarily shaped raceway elements can bemanufactured without great expense in terms of manufacturing technology.Here the individual dimensions of the raceway elements can be achievedvia a simple software controlling or programming of a control devicecontrolling the laser cutting. An individual manufacturing of punchingtools that are adapted to the respective raceway can thus be omitted.Raceway elements made of plate, in particular metal plate, are therebymore economical even with smaller quantities.

If the raceway element or the plurality of raceway elements are to bemanufactured from a metal plate having a large surface, then a lasercutting device can be relatively easily designed to be movable relativeto the metal plate. In addition, forces acting normal to the plane ofthe metal plate, as is the case with a punching process, that could leadto an undesirable deforming of the edges of the raceway elements, do notarise here. In addition, a particularly precisely shaped edge of theraceway element can be formed by laser cutting, so that, in comparisonto a punched edge, for example, a machining post-processing step cangenerally be omitted. In this way the manufacturing is simplified. Dueto the laser cutting, the outer contour can be particularly easilyshaped individually so that different shapes for the raceway element canbe manufactured with one and the same tool and from a metal plate of onesize.

In a first state of the metal panel the raceway element preferably hasan outer contour in the shape of an essentially rectangular strip,wherein two opposing sides are configured as joint edges that areconnected to each other in a second state in order to form an annularraceway element. In particular, the essentially rectangular strip hastwo long edges and two short edges, wherein the short edges arepreferably configured as joint edges.

According to a further embodiment, the joint edges are formed bypunching, and the rest of the outer contour, i.e., the two long edges,are formed by laser cutting. Since the joint edges usually have ashorter length in comparison to the rest of the contour of the racewayelement, the negative effects of the punching process can be ignored andtheir positive properties prevail. In addition, a greater heatdevelopment can arise due to the laser cutting, which can lead to ahardening of the edge, which negatively affects a possible later weldingof this edge. By punching of the joint edges that are connected to eachother for the manufacturing of a finished raceway element, in particularwelded, a negative influencing by the possible heat development of thelaser cutting, which can generate the above-mentioned hardenings thatnegatively influence a welding seam, can be prevented.

As mentioned above, according to a further embodiment the one joint edgeof the raceway element is connected via a material-bonded,interference-fit, or friction-fit connection to the other joint edge ofthe raceway element in order to obtain the annular raceway element. Herein particular a material-bonded connection is advantageous, such as, forexample, a welded connection. Here in particular a laser welding ispreferred as opposed to a resistance welding, since the melting materialpushed off during resistance welding can cause protrusions.

According to a further embodiment, the raceway element can alternativelyor additionally include at least one chamfer. The chamfer is preferablyformed along the joint edges. Here the at least one chamfer can receivethe protrusions, such as, for example, upper beads, that arise duringwelding and thus prevent the slipping or rolling of the rolling elementson the raceway element from being disturbed.

According to one alternative embodiment, in a first state of the sheetmetal panel the raceway element has an outer contour in the shape of aparallelogram having two sides extending obliquely with respect to acircumferential direction, wherein the two sides extending obliquelywith respect to the circumferential direction are configured as jointedges that are connected to each other in a second state in order toform an annular raceway element.

This has the advantage in particular that the course of the two jointedges connected to each other, i.e., in particular a welding seam,extends obliquely with respect to the circumferential direction of thefinished raceway element, so that in particular in the case of rollingelements that have a line-shaped abutment against the finished racewayelement (rolling elements with linear contact), each can only encountera disturbance at a point, but not over the entire line-shaped abutment,when these rolling elements run over the joint edges connected to eachother. A connecting point for the raceway element can advantageously beprovided, which connecting point minimizes a disturbance of a lineartouching or of a linear contact of a rolling rolling-element, inparticular in comparison to an exclusively radially extending jointedge, by the rolling contact of the rolling element continuouslyoverrunning the connecting point.

In particular, at least one of the joint edges can be configured atleast partially as a first alignment element and/or include at least onefirst alignment element. Here the first joint edge can be alignedradially, axially, and/or circumferentially with respect to the secondjoint edge, such that the joint edges to be connected are alignedprecisely flush prior to the connecting process, which can be, forexample, a welding process. Consequently the risk can be precluded or atleast significantly reduced that the joint edges are offset with respectto each other in the connected state. The first and the second jointedge preferably each include an alignment element. The alignmentaccuracy can thereby be increased.

The second joint edge preferably includes a second alignment elementand/or is at least partially configured as a second alignment element,wherein the second alignment element and/or the joint edge at leastpartially configured as a second alignment element is configuredcomplementary to the first alignment element, so that in the connectedstate the first joint edge and the second joint edge are alignedradially, axially, and/or circumferentially with respect to each other.Due to the complementary formation, the joint edges can be automaticallyaligned with respect to each other by the engaging one-into-the-other ofthe alignment elements or of the joint edges configured as alignmentelement.

Furthermore it is advantageous if the alignment element is configuredsuch that a movement of the joint edges with respect to each other inthe axial and/or radial direction is limited or prevented, so that theconnection process can be facilitated and carried out more precisely.For example, the alignment element can include a first and a secondsection that extend by different distances circumferentially, whereby itis prevented that, with contacting of the joint edges, the first jointedge can be displaced with respect to the second joint edge. The risk isthereby practically precluded that the joint edges are not aligned flushduring welding.

Here the alignment element can additionally serve to configure thecourse of the joint edges connected to each other such that a rollingelement having linear contact does not roll over the connecting jointedges along their entire linear contact, but rather only at partialpoints.

Thus, for example, the first joint edge can include a projectionprotruding in the circumferential direction, and the second joint edgecan include an opening complementary to the protruding projection. Thefirst joint edge can also include a projection protruding in thecircumferential direction and an opening recessed in the circumferentialdirection, and the second joint edge can include an openingcomplementary to the protruding projection and a projectioncomplementary to the recessed opening. It is also conceivable that thefirst joint edge includes a plurality of alignment elements, and thesecond joint edge includes a plurality of complementary alignmentelements corresponding to the plurality of alignment elements. Theprojection and the opening preferably have a triangular shape or asemicircular shape, or the first and second joint edge overall have awave shape. All shapes serve both for aligning and for minimizing thecontact with the over-rolling rolling element.

A further problem in the manufacturing of a raceway element from a sheetmetal panel can occur during the round bending of the strip-shapedraceway element, since in particular in the case of greater materialthicknesses the rigidity of the sheet metal panel can impede the roundbending. According to a further embodiment, the raceway elementtherefore includes a bending facilitating recess, for example, in theform of a knurling or ribbing, in order to facilitate a bending of theraceway element into ring shape. Here the bending facilitating recesscan be provided on one of the surfaces that lies opposite the surfacethat will form the raceway for the rolling elements. Alternatively oradditionally one edge can also include such a bending facilitatingrecess. Here in particular the at least one bending facilitating recesscan extend perpendicular to the circumferential direction orperpendicular to a longitudinal edge of the raceway element. The atleast one bending facilitating recess preferably extends continuouslyover an entire axial length of the finished, i.e., annular racewayelement, but extends through the total thickness of the raceway element.A plurality of bending facilitating recesses are preferably uniformlydistributed over an entire circumference of the finished, annularraceway element.

An outer contour of the raceway element preferably includes at least onemicro-connection point by which the raceway element is connected duringits manufacturing, i.e., in particular during the punching of the jointedges, to the sheet metal panel from which the raceway element ismanufactured. The at least one micro-connection point is preferablygenerated during the laser cutting, for example, by the laser beambriefly being interrupted so that an edge is not completely laser-cutand a micro-connection point remains. The at least one micro-connectionpoint can in particular make possible that a plurality of racewayelements are simultaneously formed from the sheet metal panel, but stillin the compound structure of the sheet metal panel are subjected to asurface processing, such as, for example, a hardening, annealing, or thelike, and/or a profiling, as described below. In particular, themanufacturing of the raceway elements can thereby be designed moreefficient.

Furthermore, a surface of the raceway element can be provided with aprofile, in particular for rolling elements. The profile can preferablybe concave, convex, or straight. In particular, the profile can beapplied onto the surface before the raceway element is round-bent inorder to form the finished raceway element. The profiling in particularof the raceway can thereby be simplified. For example, the profile canalready be provided in the sheet metal panel before the raceway elementis released by laser cutting and/or punching. It is also conceivablethat the raceway element is provided with the profile after its outercontour is formed by laser cutting and/or punching, but the racewayelement is still connected to the sheet metal panel via themicro-connection points. This can in particular make it possible toprovide a plurality of raceway elements with a profile in parallel. Itis also possible to provide the raceway element with a profile onlyafter the releasing of the micro-connection points.

For the case that the raceway element is configured as a raceway forrolling elements in a rolling-element bearing including an inner ring,an outer ring, and the plurality of rolling elements that are disposedbetween the inner ring and the outer ring, a flange for the rollingelements can be formed from the same sheet metal panel, wherein theflange is formed one-piece with the raceway element. In particular aconnecting of a flange, which is manufactured separately from theraceway element, can thereby be omitted, whereby a complex orienting andconnecting of the flange to the raceway element can be omitted. Afurther flange can be provided on a side that lies opposite the side onwhich the flange is formed.

The flange is preferably formed by bending. It can be advantageous herewhen at least one target bending point is formed on at least one surfaceof the raceway element in order to facilitate the bending. For example,the target bending point can be configured as a notch. However, otherforms for the target bending point are also possible.

Furthermore, a region of the raceway element that forms the flange canbe rolled and/or milled so that a cross-section of this region isflatter than a cross-section of the rest of the raceway element. Abending of the raceway element in order to form the flange can therebybe simplified.

Since problems can arise during the round bending of the raceway elementdue to the compressing or stretching of the flange necessary therefor,depending on whether the raceway element is used on an inner ring or onan outer ring, the above-mentioned bending facilitating recess canadditionally or alternatively also be formed on an outer edge of theflange in order to facilitate a bending into the ring shape. Inparticular, a plurality of bending facilitating recesses, preferably inthe form of a ribbing or knurling, can be provided that are uniformlydistributed circumferentially around the outer edge of the flange.

According to one embodiment the at least one recess is formed in theregion of the connected joint edges. Furthermore, the first and secondjoint edge can each include a first section and a second section,wherein the first section and the second section are defined by therecess, and when the first and second joint edge are connected to eachother in order to form the annular raceway element, the first sectionand the second section are disposed circumferentially offset withrespect to each other. A welding seam length can thereby be reduced,which in turn reduces the time that is required for generating thewelding seam, and reduces the costs for the welding seam, both withrespect to the working time required and with respect to the weldingmaterial required. Furthermore, the heat introduced into the racewayelement during the welding can be reduced by a shorter welding seam. Afurther advantage is that when a rolling element rolls over theconnected joint edges, contact between the joint edges and the rollingelement is minimized.

For example, the at least one recess can have an essentially elongatedshape whose longitudinal direction extends obliquely with respect to acircumferential direction of the raceway element. Furthermore, the atleast one recess can be disposed along the circumferential direction atan edge region of the raceway element. This makes possible a materialsavings, which can be undertaken in particular on a part of the racewaythat supports no loads, such as is the case, for example, with a balanceshaft.

According to a further aspect, a bearing is provided including at leastone raceway element described above. Here the bearing can preferably bea rolling-element bearing. The rolling-element bearing canadvantageously comprise two of the raceway elements described. Forexample, an inner ring and/or an outer ring of the bearing can includethe raceway element or be formed from the raceway element. The racewayelement can also be attached to the inner ring and/or the outer ring. Ofcourse, a bearing or rolling-element bearing can also be used, whereinan element, for example, a shaft, a hollow shaft, or the like, serves asinner ring, or an element, for example, a housing, serves as outer ring.For example, the bearing can be a ball bearing, a cylindrical rollerbearing, a tapered roller bearing, or the like.

According to a further aspect, a method is proposed for manufacturing araceway element described above, wherein the method includes the steps:

-   providing a sheet metal panel, and-   forming one or more raceway elements from the sheet metal panel.

Here in particular the raceway element is formed by laser cutting and/orpunching. A plurality of elements are preferably formed simultaneously,whereby the manufacturing of the raceway elements can be more efficient,which consequently reduces the manufacturing costs of each individualraceway element, so that even small quantities can be cost-effective.

Furthermore, the method for manufacturing the raceway element caninclude further steps. For example, the method can comprise one or moreof the following steps:

-   forming at least one recess in a surface with at least one of the    plurality of raceway elements, which surface is configured as a    raceway,-   applying a profile onto the raceway element, wherein the profile in    particular is concave, convex, or straight,-   folding/bending a flange for the rolling elements from the same    sheet metal panel, wherein the flange is formed one-piece with the    raceway element,-   releasing the raceway element from the rest of the sheet metal panel    by breaking of micro-connection points, via which the raceway    element is connected to the rest of the sheet metal panel after    forming of the raceway elements, provided the raceway element is    attached to the sheet metal panel by the micro-connection points    described above, wherein—when necessary-   a partial releasing of the micro-connection points is first    effected, so that the flange can be formed and subsequently the    micro-connection points that connect the raceway element to the rest    of the sheet metal panel are released after the forming of the    flange, so that during the folding/forming of the flange the raceway    element is still connected to the sheet metal panel via at least a    part of the micro-connection points,-   round bending the raceway element,-   material, friction-fit, and/or interference-fit connecting the joint    edges.

If a plurality of raceway elements are formed from a sheet metal panel,it can be advantageous in particular to arrange the raceway elements onthe sheet metal panel such that the excess material of the sheet metalpanel that is not used for a raceway element is minimized. For thispurpose, for example, the respective outer contours of the plurality ofraceway elements can be arranged on the sheet metal panel such that aregion of the outer contour that forms the at least one recess in theround-bent state of the raceway element receives a region that, in theround-bent state of the raceway element, forms a non-recessed region ofthe raceway element.

Further advantages and advantageous embodiments are specified in thedescription, the drawings, and the claims. Here in particular thecombinations of features specified in the description and in thedrawings are purely exemplary, so that the features can also be presentindividually or combined in other ways.

In the following the disclosure is described in more detail using theexemplary embodiments depicted in the drawings. Here the exemplaryembodiments and the combinations shown in the exemplary embodiments arepurely exemplary and are not intended to define the scope of theinvention. This scope is defined solely by the pending claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic depiction of a sheet metal panel including aplurality of raceway elements according to a first exemplary embodiment.

FIG. 2A is a schematic detail view of a round-bent raceway element.

FIG. 2B is a schematic detail view of a round-bent raceway element,wherein the joint edges are connected to each other.

FIG. 3 is a further exemplary embodiment of a raceway element.

FIG. 4A is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 4B is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 4C is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 5A is a raceway element according to a further exemplaryembodiment.

FIG. 5B is a raceway element according to a further exemplaryembodiment.

FIG. 5C is a raceway element according to a further exemplaryembodiment.

FIG. 5D is a raceway element according to a further exemplaryembodiment.

FIG. 6A is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 6B is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 7A is a plan view of a raceway element according to a furtherexemplary embodiment in a first state.

FIG. 7B is a plan view of the raceway element according to FIG. 7A in asecond state.

FIG. 7C is a perspective view of the raceway element from FIG. 7B.

FIG. 8A is a plan view of a raceway element according to a furtherexemplary embodiment in a first state.

FIG. 8B is a plan view of the raceway element according to FIG. 8A in asecond state.

FIG. 8C is a perspective view of the raceway element from FIG. 8B.

FIG. 9A is a plan view of a raceway element according to a furtherexemplary embodiment in a first state.

FIG. 9B is a plan view of the raceway element according to FIG. 9A in asecond state.

FIG. 9C is a perspective view of the raceway element from FIG. 9B.

FIG. 10 is a schematic process diagram of a method for the manufacturingof a raceway element according to a further exemplary embodiment.

FIG. 11 is a plan view of a plurality of the raceway elements of FIG. 9Aarranged on a panel.

DETAILED DESCRIPTION

In the following, identical or functionally equivalent elements aredesignated by the same reference numbers. The direction designationsused in the following—axial, radial, circumferential—always refer to thefinished raceway element.

FIG. 1 shows a schematic depiction of a sheet metal panel 1 including aplurality of raceway elements 2 according to a first exemplaryembodiment. Each of the raceway elements 1 has an outer contour 4. As isshown in FIG. 1, a plurality of raceway elements, even differentlydesigned, can be formed from a sheet metal panel 1. Of course, it isalso possible to form only one raceway element 2 from a sheet metalpanel 1.

As is schematically indicated in FIG. 1 by the line thickness, the outercontour 4 of a respective raceway element 2 is formed by laser cuttingand/or punching, wherein the outer contour 4 in the exemplary embodimentshown in FIG. 1 has a rectangular shape.

In particular, a first surface 5 of the raceway element 2 can beconfigured as a raceway that interacts with rolling elements rolling onit. Alternatively the first surface 5 of the raceway element 2 can beconfigured as a sliding surface that interacts with another slidingsurface such that an element serving as inner ring and an elementserving as outer ring for a bearing, or an inner ring and an outer ringof the bearing, are rotatable with respect to each other.

In the exemplary embodiment shown in FIG. 1, in a first state of thesheet metal panel 1 the raceway element 2 has an outer contour 4 in theshape of an essentially rectangular strip having two long edges 7 andtwo short edges 6. Here the two short edges 6 are configured asso-called joint edges 6-1, 6-2 that are connected to each other in asecond state in order to form the annular raceway element 2. Here theconnecting of the joint edges 6-1, 6-2 can be effected in a material,friction-fit, or interference-fit manner, wherein a material connectionis preferred, in particular by welding.

The joint edges 6-1, 6-2 are preferably formed by punching. Here thispunching of the joint edges 6-1, 6-2 can be effected prior to the lasercutting of the rest of the outer contour 4, i.e., of the two long edges7. However, punching prior to the laser cutting is preferred since themetal plate still has greater stability here.

The great advantage with combined laser cutting/punching or only withlaser cutting is that, as shown by way of example in FIG. 1, the racewayelement 2 can easily be cut-out from a large-surface sheet metal panel1. Here a plurality of raceway elements 2 can be obtained from the sheetmetal panel 1, which are dimensioned identically as shown in FIG. 1.However, it is also possible that these raceway elements 2 differ intheir dimensions.

In order to form a spatial fixing of the raceway element 2 or of theraceway elements 2 for steps, for example, occurring after the lasercutting, such as punching, bending, rolling, stamping, and to improvethe manageability of the raceway element 2, the individual racewayelements 2 can preferably each be connected to the rest of the sheetmetal panel 1 via micro-connection points 12 (FIG. 5). It can therebyalso be made possible to support the plurality of raceway elementsformed from the sheet metal panel 1 in a flat state, by the racewayelements 2 still remaining connected to the sheet metal panel 1 via themicro-connection points 12. These micro-connection points 12 may bereleased only when the respective raceway element 2 is required. Themicro-connection points 12 are preferably configured such that areleasing of the raceway element 2 from the sheet metal panel 1 ispossible by a simple manual breaking of the micro-connection points 12.Mechanical and/or machine breaking or removing is also possible.

In order to also facilitate the storing and handling or the subsequentfurther processing, a plurality of raceway elements 2 can be groupedinto a “Cluster” 14, wherein stabilizing metal-plate regions 16 areformed between the clusters 14. The stabilizing metal-plate regions 16can thus prevent the unintentional release of the raceway elements 2from the sheet metal panel 1. To provide one of the raceway elements 2it can be provided that first the respective cluster 14 is completelyreleased from the rest of the metal plate 1, and in a subsequent stepthe desired raceway element 2 is separated from the rest of the cluster14.

In order to form the finished raceway element 2, it must be brought intoa desired shape (FIG. 2A), for example, by round bending, after it hasbeen cut out from the sheet metal panel 1. The result of such a roundbending is schematically shown in FIG. 2A, wherein for the sake ofsimplicity only a part of the round-bent raceway element 2 is shown.

The two joint edges 6-1, 6-2 can be assembled via a connection, forexample, a welded connection 8 as mentioned above, in order to form thefinished annular raceway element 2. FIG. 2B shows the round-bent racewayelement 2 after the two joint edges 6-1, 6-2 are connected to each otherby the welded connection 8. In order to prevent excess material fromprotruding during connecting, in particular over the surface configuredas raceway 5, as can be seen in the exemplary embodiment depicted ofFIG. 2A or 2B, chamfers 10-1, 10-2, 10-3, 10-4 can be formed along thejoint edges 6-1, 6-2. These chamfers serve for receiving excess materialthat arises during the welding without protrusions of the weldingmaterial impairing the raceway 5.

FIG. 3 shows a further exemplary embodiment of a raceway element 2. Theround bending of the strip-shaped raceway element 2 can be problematicin particular in the case of a sheet metal panel 1 having greatermaterial thickness. Here the round bending of the raceway element 2 canbe facilitated with the aid of bending facilitating recesses 19 that arepresent in the exemplary embodiment depicted in the form of a knurling18. Here the knurling 18 is preferably provided on a side 9 opposite thesurface 5 configured as a raceway. Furthermore, a rolling element 20 isdepicted in FIG. 3, which rolling element 20 rolls on the raceway 5.

The knurling 18 comprises a plurality of recesses that are distributedcircumferentially over the raceway element 2 and extend perpendicular tothe circumferential direction or perpendicular to a long edge 7 of theraceway element 2. The recesses 19 of the knurling 18 preferably extendcontinuously over an entire axial length of the finished, i.e., annularraceway element 2, but do not extend through the entire thickness 22 ofthe raceway element.

FIGS. 4A, 4B, 4C each show a cross-section through a raceway element 2according to further exemplary embodiments. Depending on theapplication, the raceway element 2 can be provided with a profile forthe raceway 5. FIG. 4A shows a raceway element 2 having a straightraceway profile. FIG. 4B shows a cross-section of a raceway element 2having a crowned or convex profile that is used, for example, in needleroller bearings. In contrast thereto, FIG. 4C shows a cross-section of araceway element 2 having a hollow-shaped or concave profile that isused, for example, with toroidal rollers. The profile can be appliedonto the sheet metal panel 1 prior to the cutting out or final releasingof the raceway element 2.

In order to ensure, for example, that the rolling elements 20 do notcontact along the entire linear contact 21 of the connected joint edges6-1, 6-2 in the case of rolling elements having a linear contact, i.e.,a line-shaped abutment against the raceway 5, such as, for example,needle rollers, cylindrical rollers, tapered rollers, or the like, theconnected joint edges 6-1, 6-2 in the exemplary embodiments that areshown in FIGS. 5A to 5D are disposed obliquely with respect to thelinear contact 21 or obliquely with respect to the long edge 7 of theraceway element, which long edge 7 is parallel to the circumferentialdirection of the annular raceway element 2.

FIG. 5A shows a raceway element 2 in a first state on the sheet metalpanel 1, the one outer contour 4 in the shape of a parallelogram havingtwo short sides 6 extending obliquely with respect to a circumferentialdirection; the short sides 6 are configured as joint edges 6-1, 6-2 thatare connected to each other in a second state in order to form anannular raceway element.

In the raceway elements 2 shown in FIGS. 5B to 5D, the joint edges areadditionally configured as a first or second alignment element 26-1,26-2, using which the first joint edge 6-1 is aligned radially, axially,and/or circumferentially with respect to the second joint edge 6-2, suchthat the joint edges 6-1, 6-2 to be connected are aligned preciselyflush prior to the connection process. As is shown in FIGS. 5B to 5D,the first and the second joint edge 6-1, 6-2 preferably have mutuallycomplementary alignment elements; here the alignment elements 26-1, 26-2in FIG. 5B have a triangular shape, in FIG. 5C a semicircular shape, andin FIG. 5D a wave shape.

As can be seen from the depicted exemplary embodiments, the alignmentelement 26-1, 26-2 can additionally serve to configure the course of thejoint edges connected to each other such that a rolling element 20having linear contact 21 does not roll over the connected joint edges6-1, 6-2 along its entire linear contact 21, but rather only at partialpoints.

For the case that the raceway element 2 forms a raceway 5 for rollingelements 20 in a rolling-element bearing including an inner ring, anouter ring, and the plurality of rolling elements that are disposedbetween the inner ring and the outer ring, a flange 28 for the rollingelements 20 is provided in the exemplary embodiments shown in FIGS. 6Aand 6B, which flange 28 is formed from the same sheet metal panel 1 andis one-piece with the raceway element 2.

The flange 28 is formed by bending, wherein a target bending point 24 isprovided both in the exemplary embodiment in FIG. 6A and in theexemplary embodiment in FIG. 6B. In the exemplary embodiment in FIG. 6B,the target bending point is obtained such that a region 30 of theraceway element 2, which region 30 forms the flange, is rolled and/ormilled such that a cross-section of this region 30 is flatter than across-section of the rest of the raceway element 32. The flange 24 issubsequently formed by folding, turning up, and/or bending of the region30. FIG. 6A shows an alternative target bending point 24 in the form ofa notch.

Since depending on whether the raceway element 2 is used on an innerring or on an outer ring, problems can arise during round bending of theraceway element 2 due to the compression or stretching of the flange 28,a knurling can also be provided on an outer edge 34 of the flange 28 inorder to simplify the bending of the raceway element 2 even with anexisting flange 28.

FIGS. 7 to 9 show exemplary embodiments for a raceway element includingat least one recess 40 that extends continuously through the surface ofthe raceway element 2, which surface is formed as raceway 5. Here FIGS.7A, 8A, and 9A each show the raceway element 2 in a first state beforethe joint edges are connected to each other in order to form the annularraceway element 2. FIGS. 7B, 8B, and 9B show the respective exemplaryembodiment of the annular raceway element 2 in a plan view, and FIGS.7C, 8C, and 9C show the respective exemplary embodiment of the annularraceway element 2 in perspective view.

FIG. 7 shows a raceway element 2 in which the recess 40 is formed as alubricant reservoir in order, for example, to improve the lubricationconditions for the rolling elements 20 and achieve a weight reduction bymaterial saving. Here the recess 40 is formed in the region of theconnected joint edges 6-1, 6-2, wherein the first and second joint edge6-1, 6-2 each include a first section 42 and a second section 44. Thefirst section 42 and the second section 44 are defined by the recess 40and are configured such that in the annular state of the raceway element2 (FIGS. 7B, 7C), the first section 42 and the second section 44 aredisposed circumferentially offset with respect to each other.

Furthermore, the at least one recess also makes it possible to reducematerial, which can on the one hand reduce the costs of the racewayelement, and on the other hand reduces the weight of the racewayelement.

FIG. 8 shows a raceway element 2, wherein the recess 40 is disposed onan edge region of the raceway element 2 along the circumferentialdirection, whereby, for example, a material saving can be achieved in apart of the raceway 5 that supports no loads, such as, for example, witha balance shaft. Furthermore, FIG. 8 in turn shows an oblique course ofthe connected joint edge 6-1, 6-2, which minimizes the contact betweenrolling elements having linear contact and joint edges 6-1, 6-2.

Similar to FIG. 7, FIG. 9 shows a raceway element 2, wherein the recess40 is formed in the region of the connected joint edges 6-1, 6-2 anddefines a first section 42 and a second section 44 of the first andsecond joint edge 6-1, 6-2, wherein in the annular state of the racewayelement 2 (FIGS. 9B, 9C) the first and second section 42, 44 aredisposed circumferentially offset with respect to each other.

FIG. 11 shows that the respective outer contours of the plurality ofraceway elements 2 of FIG. 9A can be arranged on a sheet metal panelsuch that a region of the outer contour that forms the at least onerecess in the round-bent state of the raceway element receives a regionthat, in the round-bent state of the raceway element, forms anon-recessed region of the raceway element.

Also in the exemplary embodiments shown in FIG. 7 and FIG. 9, inaddition to minimizing the length of the joint edges, an obliquepositioning of the joint edges can also be provided in order to furtherreduce the contact between rolling elements having linear contact andconnected joint edges.

FIG. 10 shows a schematic diagram of a method 100 for manufacturing araceway element 2 described above. Here the method comprises a step S1,in which a sheet metal panel 1 is provided. Subsequently in a step S2,one or more raceway elements 2 are formed from the sheet metal panel 1by laser cutting and/or punching. A plurality of elements 2 arepreferably formed simultaneously, whereby the manufacturing of theraceway elements 2 can be more efficient, which consequently reduces themanufacturing costs of each individual raceway element 2, so that evensmall quantities can be cost-effective.

Depending on the raceway element 2 required, the method 100 can includea step S3, in which at least one recess 40 is formed in a surfaceconfigured as raceway 5. Furthermore, in a step S4 a profile can beapplied onto the raceway element 2, wherein the profile is in particularconcave, convex, or straight. Provided the raceway element 2 is stillconnected to the sheet metal panel 1 by micro-connection points 12, in astep S5 these micro-connection points 12 can be released by breaking.However, step S5 can also take place at another point during the method.

Furthermore, the method 100 can include a step S6, in which a flange 28for the rolling elements is formed from the same sheet metal panel, andone-piece with the raceway element, by folding or bending. In order tofinally complete the raceway element 2, in a step S7 the raceway element2 is formed by round bending, and completed in a step S8 by connectingof the joint edges 6-1, 6-2.

In summary a raceway element can be manufactured particularlyeconomically by the raceway element being formed by laser cutting and/orpunching, whereby an individual manufacturing is possible without toolsthat are specifically matched to the dimensions of the raceway element.The raceway element can advantageously be manufactured from a metalplate, wherein during manufacturing the raceway element is stillconnected to the rest of the metal plate via micro-connection points.

Representative, non-limiting examples of the present invention weredescribed above in detail with reference to the attached drawings. Thisdetailed description is merely intended to teach a person of skill inthe art further details for practicing preferred aspects of the presentteachings and is not intended to limit the scope of the invention.Furthermore, each of the additional features and teachings disclosedabove may be utilized separately or in conjunction with other featuresand teachings to provide improved bearing raceway elements.

Moreover, combinations of features and steps disclosed in the abovedetailed description may not be necessary to practice the invention inthe broadest sense, and are instead taught merely to particularlydescribe representative examples of the invention. Furthermore, variousfeatures of the above-described representative examples, as well as thevarious independent and dependent claims below, may be combined in waysthat are not specifically and explicitly enumerated in order to provideadditional useful embodiments of the present teachings.

All features disclosed in the description and/or the claims are intendedto be disclosed separately and independently from each other for thepurpose of original written disclosure, as well as for the purpose ofrestricting the claimed subject matter, independent of the compositionsof the features in the embodiments and/or the claims. In addition, allvalue ranges or indications of groups of entities are intended todisclose every possible intermediate value or intermediate entity forthe purpose of original written disclosure, as well as for the purposeof restricting the claimed subject matter.

REFERENCE NUMBER LIST

-   1 Sheet metal panel-   2 Raceway element-   3 Outer contour-   4 Surface-   6-1, 6-2 Joint edge-   7 Long edge-   8 Connection-   9 Surface-   10-1-10-4 Chamfer-   12 Micro-connection point-   14 Cluster-   16 Metal-plate regions-   18 Knurling-   19 Bending facilitating recess-   20 Rolling element-   21 Linear contact-   22 Thickness-   24 Target bending point-   26-1, 26-2 Alignment element-   28 Flange-   30, 32 Region-   34 Edge-   40 Recess-   42 First section-   44 Second section-   100 Method-   S1-S8 Method steps

What is claimed is:
 1. A raceway element for a rolling-element bearing,wherein the rolling-element bearing comprises an inner ring, an outerring, and a plurality of rolling elements that are disposed between theinner ring and the outer ring, wherein the raceway element is configuredas an inner ring or as an outer ring, or is configured to be attachableto an inner ring or outer ring of the bearing, wherein at least onesurface of the raceway element is configured as a raceway for therolling elements, and wherein the raceway element is formed from a sheetmetal panel having at least one recess formed in the surface configuredas the raceway.
 2. The raceway element according to claim 1, wherein theraceway element includes at least one first joint edge and at least onesecond joint edge directed in a circumferential direction, the first andsecond joint edges being configured to be connected to each other inorder to form the raceway element, and wherein the at least one recessis formed in a region of the connected first and second joint edges. 3.The raceway element according to claim 1, wherein the at least onerecess is configured as a lubricant reservoir.
 4. The raceway elementaccording to claim 1, wherein the at least one recess is elongated witha longest dimension extending extends obliquely with respect to acircumferential direction of the raceway element.
 5. The raceway elementaccording to claim 2, wherein the at least one recess comprises a firstrecess portion in the first joint edge and a second recess portion inthe second joint edge, the first recess portion being circumferentiallyoffset from the second recess portion when the first joint edge isconnected to the second joint edge.
 6. The raceway element according toclaim 2, wherein the at least one recess extends into an axially facingedge of the raceway element.
 7. The raceway element according to claim1, wherein the raceway element is formed by laser cutting and/orpunching.
 8. A rolling element bearing, including: at least one racewayelement according to claim 1 mounted on a radially inner circumferentialsurface or on a radially outer circumferential surface and a pluralityof rolling elements mounted on the raceway element.
 9. A methodcomprising: separating at least one strip of sheet metal from a sheetmetal panel by a combination of punching and laser cutting, the at leastone strip having a width and a length greater than the width and a firstjoint edge and a second joint edge spaced apart in a length directionand a first side edge and a second side edge spaced apart in a widthdirection, the at least one strip being shaped such that when the atleast one strip is bent into a ring such with the first side edge incontact with the second side edge side, the ring will include a recess;and bending the at least one strip into the ring and materially bondingthe first joint edge to the second joint edge.
 10. The method accordingto claim 9, further including: installing the ring on a radially innercircumferential surface or a radially outer circumferential surface; andmounting a plurality of rolling-elements on the ring.
 11. The methodaccording to claim 10, wherein the at least one strip comprises aplurality of strips each having an outer contour formed by the first andsecond joint edges and the first and second side edges, the plurality ofstrips being arranged on the sheet metal panel such that such that aregion of the outer contour that forms the at least one recess in around-bent state of the raceway element of a first one of the pluralityof strips receives a portion of a second one of the plurality of stripsthat, in the round-bent state of the raceway element, forms anot-recessed region of the raceway element.
 12. The method according toclaim 10, wherein the first and second joint edges are formed by thepunching and the first and second side edges are formed by the lasercutting.